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Re: Engine turning

To: Enrique Claure <>
Subject: Re: Engine turning
From: Jurgen Hartwig <>
Date: Wed, 12 May 1999 11:18:13 -0400

Enrique Claure wrote:
> Hi List, I just finished building the bottom of my 77B engine and cant stop
> wodering how smooth it should turn when I turn the crank. I noticed that
> when the crank and rods are in a vertical position the engine turns easier.
> I had the crank and block checked for alignment, got a new crank,bearings,
> pistons, rings,cam,timing sprockets,chain,tensioner, quality torq rench.
> Any tips before I put the oil pan will be appreciated, Regards, Enrique

Did you use plastigauge to check the clearances in your crank and rod
bearings?  This is part of the work required for a good rebuild.  Even
if you didn't do this, you can still get an idea of clearances when you
are building up.  After you bolt in the crank and torque it down, you
should be able to rotate the crank with minimal effort.  I'm not saying
it's going to freewheel, but it will take only minor force to get it to

When you start to add pistons and rods, your should periodically rotate
the crank.  If it binds or you start to see a lot of force, then
something is wrong.  Once you have the 4 pistons in, you should still be
able to rotate the crank, but it's going to take some heft.  Remember
that you are fighting friction in the piston bores now.  This all adds
up.  You should be able to turn the whole mechanism with light to medium
pressure on a 16" breaker bar or torque wrench, and note that it will
take a great amount of force to break the mass free, but afterwards, it
should rotate with less force.  I'm sorry I can't comment on exact
force.  The exact force depends on your specific engine build-up. 

When I built up the V8, all tolerances were well within spec.  In fact,
we were towards the loose end of the spectrum.  Turning the crank over
was a task in itself.  All of those piston rings created a lot of

When you were born you cried
And the world rejoiced.
Live your life so in death you rejoice
And the world cries.

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